Bilateral anterior thalamic symmetrical infarction is very rarely observed in clinical practice and has rarely been reported in the literature. In this paper we introduce a patient with bilateral anterior thalamic symmetrical infarction and discuss his symptoms, treatment process, and follow-up visit results, as well as the potential pathological mechanisms of the disease.A 71-year-old male had a sudden cognitive decline four days prior to medical consultation. The patient's brain MRI showed symmetrical high signals in the anterior part of both sides of the thalamus. The patient's head MRV and immunological tests were normal, and we considered that this patient had a rare case of bilateral anterior thalamic infarction. After 10 days of anti-platelet aggregation that lowered blood lipids and improved circulation, the patient's symptoms significantly abated. Two years later, we found through telephone follow-up that the patient's symptoms had not relapsed substantially and that he was able to perform self-care, having only continued to suffer a slight decline in short-term memory.For patients with bilateral prethalamic lesions who have only acute cognitive impairment, if the lesions conform to the blood supply area of both thalamic nodular arteries and DWI shows a high signal, the diagnosis of acute cerebral infarction should be considered, and the standard treatment plan for cerebral infarction should be given as soon as possible.© 2023. The Author(s).